Method of providing tactile feedback and electronic device

ABSTRACT

A method includes detecting a touch on a touch-sensitive display, determining when a touch value associated with the touch meets a first touch threshold, determining a first period of time between detecting the touch and when the touch value meets the first touch threshold, and providing a first tactile feedback when the first period of time is meets a first time threshold.

FIELD OF TECHNOLOGY

The present disclosure relates to electronic devices, including but notlimited to portable electronic devices having touch-sensitive displaysand their control.

BACKGROUND

Electronic devices, including portable electronic devices, have gainedwidespread use and may provide a variety of functions including, forexample, telephonic, electronic messaging and other personal informationmanager (PIM) application functions. Portable electronic devices includeseveral types of devices including mobile stations such as simplecellular telephones, smart telephones, wireless PDAs, and laptopcomputers with wireless 802.11 or Bluetooth capabilities.

Portable electronic devices such as PDAs or smart telephones aregenerally intended for handheld use and ease of portability. Smallerdevices are generally desirable for portability. A touch-sensitivedisplay, also known as a touchscreen display, is particularly useful onhandheld devices, which are small and have limited space for user inputand output. The information displayed on the touch-sensitive displaysmay be modified depending on the functions and operations beingperformed. With continued demand for decreased size of portableelectronic devices, touch-sensitive displays continue to decrease insize.

Improvements in devices with touch-sensitive displays are desirable.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram of a portable electronic device in accordancewith the present disclosure.

FIG. 2 illustrates a front view of a portable electronic device inaccordance with the present disclosure.

FIG. 3 illustrates a cross-sectional view through the line 202 of FIG. 2in accordance with the present disclosure.

FIG. 4 is a block diagram showing components of the portable electronicdevice in accordance with the present disclosure;

FIG. 5 is a flowchart illustrating a method of providing tactilefeedback in accordance with the present disclosure.

FIG. 6 illustrates examples of locations of touches on a touch-sensitivedisplay of a portable electronic device in accordance with the presentdisclosure.

FIG. 7 and FIG. 8 illustrate examples of timing of touches on atouch-sensitive display of a portable electronic device in accordancewith the present disclosure.

FIG. 9 illustrates a flowchart illustrating a method of providingtactile feedback in accordance with the present disclosure.

DETAILED DESCRIPTION

The following describes an electronic device and a method of providingtactile feedback in response to touches on a touch-sensitive display ofan electronic device. One or more instances of tactile feedback may beprovided based on attributes of the touch. Providing tactile feedbackmay not be feasible or desirable at all times when tactile feedback maytypically be provided, e.g., when a touch threshold is met. Methods ofdetermining when to provide tactile feedback are described, including amethod in a two-type tactile feedback system wherein one type of tactilefeedback is provided while the other type of tactile feedback is notprovided under some circumstances, e.g., not provided at all times. Inanother example, tactile feedback is provided based on the rate of touchdetection, wherein tactile feedback is provided when time between touchcharacteristics, e.g., touch depression and touch release, meets athreshold and not provided otherwise. Methods of providing tactilefeedback are disclosed, including, for example, when thethreshold-meeting changes in a two touch values occur in a time periodthat does not meet a time threshold, providing a first tactile feedback,e.g., tactile feedback related to depression of a key of a keyboard or aswitch, and when threshold-meeting changes in a two touch values occurin a time period that meets the time threshold, providing a secondtactile feedback, e.g., tactile feedback related to release of the keyof the keyboard or the switch. In this example, the second feedback,e.g., release-related feedback, is not provided in some circumstances,such as when such touches occur very close in time to each other.

For simplicity and clarity of illustration, reference numerals may berepeated among the figures to indicate corresponding or analogouselements. Numerous specific details are set forth to provide a thoroughunderstanding of the embodiments described herein. The embodiments maybe practiced without these specific details. In other instances,well-known methods, procedures, and components have not been describedin detail so as not to obscure the embodiments described herein. Thedescription is not to be considered as limited to the scope of theembodiments described herein.

The disclosure generally relates to an electronic device, which in theembodiments described herein is a portable electronic device. Examplesof portable electronic devices include mobile, or handheld, wirelesscommunication devices such as pagers, cellular phones, cellularsmart-phones, wireless organizers, personal digital assistants,wirelessly enabled notebook computers, and the like. The portableelectronic device may also be a portable electronic device withoutwireless communication capabilities such as a handheld electronic gamedevice, digital photograph album, digital camera, or other device.

A block diagram of an example of a portable electronic device 100 isshown in FIG. 1. The portable electronic device 100 includes multiplecomponents, such as a processor 102 that controls the overall operationof the portable electronic device 100. Communication functions,including data and voice communications, are performed through acommunication subsystem 104. Data received by the portable electronicdevice 100 is decompressed and decrypted by a decoder 106. Thecommunication subsystem 104 receives messages from and sends messages toa wireless network 150. The wireless network 150 may be any type ofwireless network, including, but not limited to, data wireless networks,voice wireless networks, and dual-mode networks that support both voiceand data communications. A power source 142, such as one or morerechargeable batteries or a port to another power supply, powers theportable electronic device 100.

The processor 102 interacts with other devices, such as a Random AccessMemory (RAM) 108, memory 110, a display 112 with a touch-sensitiveoverlay 114 operably coupled to an electronic controller 116 thattogether comprise a touch-sensitive display 118, one or more actuators120, one or more force sensors 122, an auxiliary input/output (I/O)subsystem 124, a data port 126, a speaker 128, a microphone 130,short-range communications 132 and other device subsystems 134.User-interaction with a graphical user interface is performed throughthe touch-sensitive overlay 114. The processor 102 interacts with thetouch-sensitive overlay 114 via the electronic controller 116.Information, such as text, characters, symbols, images, icons, links,and other items that may be displayed or rendered on a portableelectronic device, is displayed on the touch-sensitive display 118 viathe processor 102. The processor 102 may also interact with anaccelerometer 136 that may be utilized to detect direction ofgravitational forces or gravity-induced reaction forces.

To identify a subscriber for network access, the portable electronicdevice 100 uses a Subscriber Identity Module or a Removable UserIdentity Module (SIM/RUIM) card 138 for communication with a network,such as the wireless network 150. Alternatively, user identificationinformation may be programmed into the memory 110.

The portable electronic device 100 also includes an operating system 146and software programs or components 148 that are executed by theprocessor 102 and are typically stored in a persistent, updatable storesuch as the memory 110. Additional applications or programs may beloaded onto the portable electronic device 100 through the wirelessnetwork 150, the auxiliary I/O subsystem 124, the data port 126, theshort-range communications subsystem 132, or any other suitablesubsystem 134.

A received signal such as a text message, an e-mail message, or web pagedownload is processed by the communication subsystem 104 and input tothe processor 102. The processor 102 processes the received signal foroutput to the display 112 and/or to the auxiliary I/O subsystem 124. Asubscriber may generate data items, for example e-mail messages, whichmay be transmitted over the wireless network 150 through thecommunication subsystem 104. For voice communications, the overalloperation of the portable electronic device 100 is similar. The speaker128 outputs audible information converted from electrical signals, andthe microphone 130 converts audible information into electrical signalsfor processing.

The touch-sensitive display 118 may be any suitable touch-sensitivedisplay, such as a capacitive, resistive, infrared, or surface acousticwave (SAW) touch-sensitive display, as known in the art. A capacitivetouch-sensitive display includes the display 112 and a capacitivetouch-sensitive overlay 114. The overlay 114 may be an assembly ofmultiple layers in a stack including, for example, a substrate, LCDdisplay 112, a ground shield layer, a barrier layer, one or morecapacitive touch sensor layers separated by a substrate or otherbarrier, and a cover. The capacitive touch sensor layers may be anysuitable material, such as patterned indium tin oxide (ITO).

One or more touches, also known as touch contacts or touch events, maybe detected by the touch-sensitive display 118. The processor 102 maydetermine attributes of the touch, including a location of a touch.Touch location data may include an area of contact or a single point ofcontact, such as a point at or near a center of the area of contact. Thelocation of a detected touch may include x and y components, e.g.,horizontal and vertical components, respectively, with respect to one'sview of the touch-sensitive display 118. For example, the x locationcomponent may be determined by a signal generated from one touch sensor,and the y location component may be determined by a signal generatedfrom another touch sensor. A signal is provided to the controller 116 inresponse to detection of a touch. A touch may be detected from anysuitable object, such as a finger, thumb, appendage, or other items, forexample, a stylus, pen, or other pointer, depending on the nature of thetouch-sensitive display 118. Multiple simultaneous touches may bedetected.

The actuator 120 may be depressed by applying sufficient force to thetouch-sensitive display 118 to overcome the actuation force of theactuator 120. The actuator 120 may be actuated by pressing anywhere onthe touch-sensitive display 118. The actuator 120 may provide input tothe processor 102 when actuated. Actuation of the actuator 120 providesthe user with tactile feedback.

The actuator 120 may comprise one or more piezoelectric (piezo)actuators that provide tactile feedback. FIG. 2 is front view of anexample of a portable electronic device 100. In the example shown inFIG. 2, the actuator 120 comprises four piezo actuators 120, eachlocated near a respective corner of the touch-sensitive display 118.FIG. 3 is a sectional side view of the portable electronic device 100through the line 202 of FIG. 2. Each piezo actuator 120 is supportedwithin the portable electronic device 100 such that contraction of thepiezo actuators 120 applies a force against the touch-sensitive display118, opposing any force externally applied to the display 118. Eachpiezo actuator 120 includes a piezoelectric device 302, such as apiezoelectric disk adhered to a substrate 304 such as a metal substrate.An element 306 that is advantageously at least partially flexible andcomprises, for example, hard rubber may be located between the disk 302and the touch-sensitive display 118. The element 306 does notsubstantially dampen the force applied to or on the touch-sensitivedisplay 118. In the example shown in FIG. 2 and FIG. 3, the force sensor122 comprises four force-sensors 122 located between the element 306 andthe substrate 304. The force sensors 122 are utilized to determine avalue related to the force at each of the force sensors 122 when anexternal force is applied to the touch-sensitive display 118. Thesubstrate 304 bends when the piezoelectric device 302 contractsdiametrically due to build up of voltage/charge at the piezoelectricdevice 302 or in response to an external force applied to thetouch-sensitive display 118. The voltage/charge may be adjusted byvarying the applied voltage or current, thereby controlling the forceapplied by the piezo actuators 120 on the touch-sensitive display 118.The voltage/charge on the piezo actuators 120 may be removed by acontrolled discharge current that causes the piezoelectric devices 302to expand diametrically, decreasing the force applied by the piezoactuators 120 on the touch-sensitive display 118. Absent an externalforce applied to the touch-sensitive display 118 and absent a charge onthe piezoelectric device 302, the piezo actuator 120 may be slightlybent due to a mechanical preload.

A functional block diagram of components of the portable electronicdevice 100 is shown in FIG. 4. In this example, each force sensor 122 iscoupled to a controller 402, which includes an amplifier andanalog-to-digital converter (ADC). The force sensors 122 may be, forexample, force sensing resistors in an electrical circuit such that theresistance changes with force applied to the force sensors 122. As forceapplied to the touch-sensitive display 118 increases, the resistancedecreases. This change is determined, for example, via the controller116 for each of the force sensors 122, and a value representative of theforce at each of the force sensors 122 is determined.

The piezo actuators 120 are coupled to a piezo driver 404 thatcommunicates with the controller 402. The controller 402 is also incommunication with the main processor 102 of the portable electronicdevice 100 and may receive and provide signals to and from the mainprocessor 102. The piezo actuators 120 and the force sensors 122 areoperably coupled to the main processor 102 via the controller 402. Thecontroller 402 controls the piezo driver 404 that controls thecurrent/voltage to the piezoelectric devices 302, and thus controls thevoltage/charge and the force applied by the piezo actuators 120 on thetouch-sensitive display 118. Each of the piezoelectric devices 302 maybe controlled substantially equally and concurrently. Optionally, thepiezoelectric devices 302 may be controlled separately. In the exampledescribed below, the tactile feedback described simulates depression andrelease of a dome switch. Tactile feedback may simulate other switches,actuators, keys, and so forth. Non-simulated tactile feedback may beprovided. For example, when a force applied on the touch-sensitivedisplay 118 meets a depression threshold, the voltage/charge at thepiezo actuators 120 is modified to impart a force on the touch-sensitivedisplay 118 to simulate depression of a dome switch. In another example,when the force applied on the touch-sensitive display 118 meets arelease threshold after the depression threshold is met, thevoltage/charge at the piezo actuators 120 is modified to impart a forceby the piezo actuators 120 to simulate release of a dome switch.

When a touch is detected on the touch-sensitive display, touch valuesassociated with the touches are determined. A touch value may be a valueof a characteristic or attribute of a touch, for example, a forceimparted on the touch-sensitive display 118, a displacement distance ofat least a part of the touch-sensitive display 118, an area of contactof a touch, a time duration of a touch, a number of successive taps at alocation on the touch-sensitive display 118, and so forth, or anycombination thereof.

A touch threshold is a value associated with a touch, and when a touchvalue meets the touch threshold, a function is performed. A value meetsa threshold when the value is at or beyond the threshold. For example,when the touch threshold is a force value, the force threshold mayreflect, for example, the force of a touch that actuates the actuator(s)120 or a force measured or detected by a force sensor 122, which forcemay be interpreted by the processor 102 to meet the touch threshold. Atouch threshold may be a single unit-less value that is a combination oftwo or more values related to the touch, e.g., duration and force.Multiple touch thresholds may be applicable for a touch, and differentvalues of touch thresholds may be associated with different functions orinput. Different touch thresholds may be associated with different touchcharacteristics.

Multiple threshold-meeting changes for simultaneous or near-simultaneoustouches may occur within a very short period of time, for example, lessthan 15 ms. In such situations, tactile feedback for one of thethreshold-meeting changes may be delayed as tactile feedback for anotherthreshold-meeting change is provided. Tactile feedback in suchsituations may be confusing, or may not be received, for example, whentouches end before the tactile feedback is provided. In othersituations, providing tactile feedback may be difficult or impracticaldue to touch data processing delays or hardware constraints of theportable electronic device 100.

A method includes detecting, at a first time, a first touch associatedwith a first value that meets one of a first touch threshold and asecond touch threshold; detecting, at a second time, a second touchassociated with a first value that meets one of the first touchthreshold and the second touch threshold; providing first tactilefeedback at the first time; and providing second tactile feedback at thesecond time when the time period between the first time and the secondtime meets a time threshold.

The following describes examples of providing tactile feedback whenmultiple threshold-meeting changes occur for simultaneous ornear-simultaneous touches, e.g., touches that occur within a very shortperiod of time, such as 20 ms or less.

A flowchart illustrating a method of controlling the electronic device100 to provide tactile feedback is shown in FIG. 5. The method may becarried out by software executed by, for example, the processor 102.Coding of software for carrying out such a method is within the scope ofa person of ordinary skill in the art given the present description. Themethod may contain additional or fewer processes than shown and/ordescribed, and may be performed in a different order. Computer-readablecode executable by at least one processor of the portable electronicdevice to perform the method may be stored in a computer-readablemedium. In the example of FIG. 5, the touch values comprise forcevalues, and the tactile feedback comprises simulation of depression andrelease of a key or switch. Information is displayed 502 on the display112. The information may be from an application, such as a web browser,contacts, email, calendar, music player, spreadsheet, word processing,operating system interface, and so forth.

When two touches are detected 504 on the touch-sensitive display 118,the touch locations are determined. In the example shown in theflowchart of FIG. 5, the touch value is a force value associated withthe force imparted by a touch on the touch-sensitive display 118, andthe touch threshold is a force threshold. The tactile feedback providedin this example simulates depression and release of a dome switch, i.e.,two different types of tactile feedback are provided. Signals received506 from the force sensors 122 are utilized to determine 508 forcevalues associated with the touches. The force values associated with thetouches may be determined based on the locations of the force sensorsand the relative locations of the touches, utilizing, for example, aforce balance. During a scan, the touch values, such as force values,associated with the touches are determined utilizing signals receivedfrom the touch sensors, such as force sensors. Scans are performed atregular intervals in time, e.g., 10 to 15 ms.

For a touch, a comparison is made between the force value associatedwith the touch determined at 508 and the previously determined forcevalue associated with the touch, e.g., from the previous scan, to detect510 any changes in the force value associated with the touches. When nochange is detected 510 in the force values associated with the twotouches from the previous scan to the current scan, the processcontinues at 520. When a change is detected 510 in a force valueassociated with a touch, a determination is made 512 whether the changein force value associated with the touch is a threshold-meeting change.A force value meets a threshold when the force value is at or beyond thethreshold. When the force value associated with a touch meets a hightouch threshold at 512, such as a depression threshold, when the forcevalue associated with a touch from a previous scan did not meet thetouch threshold, e.g., the depression threshold, tactile feedback isprovided 514, and the process continues at 520. The tactile feedbackmay, for example, simulate depression of a switch, as described above.When the touch threshold is not met at 512, the process continues at512.

When the force value associated with a touch meets a low touch thresholdat 516, such as a release threshold, when a force value from a previousscan did not meet the touch threshold, e.g., the release threshold,tactile feedback is provided 518. The tactile feedback may, for example,simulate release of a switch. The process continues at 520.

Touch activity is detected at 520 when touch contact for one or both ofthe touches is maintained on the touch-sensitive display 118. When touchcontact continues, the touch locations are determined and the processcontinues at 506. When both touches are discontinued, the processcontinues at 504.

Tactile feedback may be provided for only one of two touches whenthreshold-meeting changes in touch values are detected within a timethreshold. The time threshold may be substantially the same as theinterval of time between scans for or determinations of touch values.Alternatively, the time threshold may be a fixed or variable period oftime, which may be selected or entered by a user. Tactile feedback maybe provided for only one of the touches when threshold-meeting changesare detected within the time threshold for both touches. When the timebetween detecting a threshold-meeting change in touch value for onetouch and detecting a threshold-meeting change in touch value foranother touch meets the time threshold, tactile feedback for boththreshold-meeting changes may be provided.

Examples of two touches on a touch-sensitive display 118 of a portableelectronic device 100 are illustrated in FIG. 6. In the example of FIG.6, a virtual keyboard is rendered on the touch-sensitive display 118,the touch values comprise force values, and the tactile feedbackcomprises simulation of depression and release of a key or switch. Atouch is detected at a location 602 on the touch-sensitive display 118that is associated with the letter “T” as shown in the upperillustration of FIG. 6. The values from the force sensors are utilizedto determine a force value associated with the touch. In this example,the force value is determined to be a depression threshold-meetingchange, and tactile feedback is provided that simulates depression of aswitch utilizing the actuators 120. Another touch is detected at alocation 604 on the touch-sensitive display 118 that is associated withthe letter “H” as shown in the middle illustration of FIG. 6. Thesignals received from the force sensors 122 are utilized to determineforce values for each of the touches 602, 604. At this time in theexample, the force value associated with the “T” touch decreases to avalue that meets the release threshold, and within a very short periodof time, the force value associated with the “H” touch increases to avalue that meets the depression threshold. The force value associatedwith the “H” touch is a depression threshold-meeting change and tactilefeedback is provided that simulates depression of a switch utilizing theactuators 120. Tactile feedback is not provided in response to detectingthe change in the force value associated with the “T” touch. The “T”touch ends without further tactile feedback.

The signals received from the force sensors 122 are utilized todetermine the force value associated with the remaining touch at the “H”location 604 shown in the lower illustration of FIG. 6. The change inforce value associated with the touch 604 is a release threshold-meetingchange, and tactile feedback is provided that simulates release of aswitch utilizing the actuators 120.

Examples of timing of touches on the touch-sensitive display 118 areshown in FIG. 7 and FIG. 8. In these examples, the touch values areforce values, and the tactile feedback comprises simulation ofdepression and release of a key or switch. In the examples shown, thearrows directed toward the horizontal line represent a threshold-meetingchange in force value from below the depression threshold to meet thedepression threshold, for example, when a user depresses thetouch-sensitive display 118. The arrows directed away from thehorizontal line represent a threshold-meeting change in force value fromnot meeting the release threshold to meeting the release threshold, forexample, when a user releases the touch-sensitive display 118 afterdepressing it. The points in time, t1, t2, t3, t4, and t5, represent thetimes at which signals are received from the force sensors 122, whichpoints in time may be referred to as scan times. The time intervalsbetween these points may be predetermined, e.g., fixed or variable basedon a calculation, table look-up, or user entry.

As illustrated in FIG. 7, touch signals are received at t1, and nochanges in force values are identified for two touches detected on thetouch-sensitive display 118. Between t1 and t2, a force value associatedwith one of the two touches meets the depression threshold, asillustrated by the arrow 702. The change in force value is determinedfrom the signals at t2, and tactile feedback is provided to simulatedepression of a switch at t2. Between t2 and t3, a force valueassociated with the touch meets the release threshold, as illustrated bythe arrow 704. The change in force value is determined from the signalsat t3, and tactile feedback is provided to simulate release of a switch.Between t3 and t4, a force value associated with the other touch of thetwo touches meets the depression threshold, as illustrated by the arrow706. The change in force value is determined from the signals at t4, andtactile feedback is provided to simulate depression of a switch. In theperiod of time between t4 and t5, a force value associated with thetouch meets the release threshold, as illustrated by the arrow 708. Thechange in force value is determined from the signals at t5, and tactilefeedback is provided to simulate release of a key or switch.

As illustrated in FIG. 8, touch signals are received at t1, and nochanges in force values are identified for two touches detected on thetouch-sensitive display 118. In the period of time between t1 and t2, aforce value associated with one of the touches meets the depressionthreshold, as illustrated by the arrow 802. The change in force value isdetermined from the signals at t2, and tactile feedback is provided tosimulate depression of a switch. In the period of time between t2 andt3, a force value associated with the touch meets the release threshold,as illustrated by the arrow 804, and a force value associated with theother touch meets the depression threshold, as illustrated by the arrow806. The changes in force values are determined from the signals at t3.In response to determining the changes in force values, tactile feedbackis provided to simulate depression of a switch. Tactile feedback is notprovided to simulate release of a switch. In the period of time betweent3 and t4, a force value associated with the other touch meets therelease threshold, as illustrated by the arrow 708. The change in forcevalue is determined from the signals received at t4, and tactilefeedback is provided to simulate release of a switch.

A threshold-meeting change in a force value associated with a touch maybe ignored, i.e., no tactile feedback is provided when anotherthreshold-meeting change in force value is detected within apredetermined period of time. In the examples of FIG. 6, thepredetermined period of time is the period of time between receivingsignals from the force sensors 122, e.g., from a previous scan to thecurrent scan. Optionally, the predetermined period of time may be apreset time or the time between a preset number of scans; a fixed periodof time set by a user; a default time stored in the device; or a valuebased on the cumulative time between signals sent by the force sensors,time to determine the force values and changes in force values, and timeto provide tactile feedback.

Reducing the number of instances of providing tactile feedback and, inparticular, not providing tactile feedback for one of twothreshold-meeting touches detected within a predetermined period oftime, reduces confusing tactile feedback provided to the user of thedevice and decreases power consumption.

A flowchart illustrating another method of providing tactile feedback isshown in FIG. 9. The method may be carried out by software executed by,for example, the processor 102. Coding of software for carrying out sucha method is within the scope of a person of ordinary skill in the artgiven the present description. The method may contain additional orfewer processes than shown and/or described, and may be performed in adifferent order. Computer-readable code executable by at least oneprocessor of the portable electronic device to perform the method may bestored in a computer-readable medium. In the example of FIG. 5, thetouch values comprise force values, and the tactile feedback comprisessimulation of depression and release of a key or switch. Information isdisplayed 902 on the display 112. The information may be from anapplication, such as a web browser, contacts, email, calendar, musicplayer, spreadsheet, word processing, operating system interface, and soforth.

When a touch is detected 904 on the touch-sensitive display 118, thetouch location is determined. The touch signals from the force sensors122 are utilized to determine 906 a force value associated with thetouch. A determination is made 908 whether the force value meets a highthreshold, e.g., a depression threshold. As described above, a forcevalue meets a threshold when the force value is at or beyond thethreshold. When the force value does not meet the high threshold, theprocess continues at 906. When the force value meets the high threshold,the depression time is determined 910, which is the time betweendetecting the touch at 904 and determining that the force value meetsthe high or depression threshold at 908. The depression time is compared912 to a predetermined time, and when the depression time is greaterthan the predetermined time, tactile feedback is provided 914. Thetactile feedback may be the simulation of depression of a switch. Whenthe depression time is not greater than the predetermined time, tactilefeedback is not provided, and the process continues at 916.

The touch signals from the force sensors 122 are utilized to determine916 a force value associated with the touch. A determination is made 918whether the force value meets a low threshold, e.g., a releasethreshold. When the force value does not meet the low threshold, theprocess continues at 916. When the force value meets the low threshold,the release time is determined 920, which is the time betweendetermining that the force value meets the high or depression thresholdat 908 and determining that the force value meets the low or releasethreshold at 918. The release time is compared 922 to a predeterminedtime, and when the release time is greater than the predetermined time,tactile feedback is provided 924. The tactile feedback may be thesimulation of release of a switch. When the release time is not greaterthan the predetermined time, tactile feedback is not provided.

Tactile feedback may not be provided where the threshold-meeting changesin force values occur very quickly. Rather than providing unnecessaryand confusing tactile feedback after a selection has occurred and aftera touch has ended, tactile feedback is not provided for a user typingvery quickly. The changes in force values may be utilized to performother functions and operations such as text entry. Reducing the tactilefeedback provided, and, in particular, not providing at least someinstances of tactile feedback, for example, for very quick touches,decreases power consumption. Utilizing any of the methods describedherein provides a user with predictable tactile feedback.

Tactile feedback may comprise a single instance of tactile feedback,such as simulation of depression of a switch, when force values formultiple touches meet a touch threshold within a short period of time.Tactile feedback may comprise a single instance of tactile feedback,such as simulation of release of a switch, when force values formultiple touches change to meet the release threshold in a short periodof time. Tactile feedback may alternatively comprise a single type offeedback, such as a pulse or vibration, rather than different types offeedback for different thresholds.

Tactile feedback may be provided at about the same time when a touchmeets a touch threshold, e.g., when the touch value is determined tomeet a touch threshold. Tactile feedback may be provided at other times.Tactile feedback is considered to be provided “at” a given time, e.g.,during or after a scan associated with the given time, at about the sametime, near, or within a short period of time that is associated with thegiven time, and so forth.

A method includes detecting at a first time a first touch associatedwith a first value that meets one of a first touch threshold and asecond touch threshold, detecting at a second time a second touchassociated with a first value that meets one of the first touchthreshold and the second touch threshold, providing first tactilefeedback at the first time, and providing second tactile feedback at thesecond time when the time period between the first time and the secondtime meets a time threshold.

An electronic device includes a touch-sensitive display, an actuator andat least one processor operably coupled to the touch-sensitive displayand the actuator, and configured to detect at a first time a first touchassociated with a first value that meets one of a first touch thresholdand a second touch threshold, detect at a second time a second touchassociated with a first value that meets one of the first touchthreshold and the second touch threshold, provide first tactile feedbackat the first time, and provide second tactile feedback at the secondtime when the time period between the first time and the second timemeets a time threshold.

Another method may include detecting a first threshold-meeting change ina touch value associated with a first touch on a touch-sensitivedisplay, detecting a second threshold-meeting change in a touch valueassociated with a second touch on the touch-sensitive display, when atleast one of the first threshold-meeting change and the secondthreshold-meeting change is a change to meet a first touch valuethreshold, providing first tactile feedback, and when the firstthreshold-meeting change and the second threshold-meeting change arechanges to meet a second touch-value threshold, providing second tactilefeedback.

Another method may include detecting a first touch at a first time and asecond touch at a second time on a touch-sensitive display, determininga first touch value associated with the first touch and a second touchvalue associated with the second touch, wherein the first touch valueand the second touch value are threshold-meeting values, when the timebetween the first time and the second time meet a time threshold,providing first tactile feedback at the first time and second tactilefeedback at the second time, and when the time between the first timeand the second time does not meet a time threshold, providing the firsttactile feedback at the first time.

Another method may include detecting a first touch and a second touchwithin a predetermined time period, wherein the first touch and thesecond touch meet at least one touch threshold, and providing firsttactile feedback in response to the detecting, and detecting a thirdtouch and a fourth touch separated by at least the predetermined timeperiod, wherein the third touch and the fourth touch meet at least onetouch threshold, and providing second tactile feedback in response todetecting the third touch and third tactile feedback in response todetecting the fourth touch.

Another method includes determining, in a first time period, a firsttouch value associated with a first touch on a touch-sensitive displayand a first touch value associated with a second touch on thetouch-sensitive display. In a second time period, a second touch valueassociated with the first touch and a second touch value associated withthe second touch are determined. When a change from the first forcevalue to the second force value associated with the first touch or thesecond touch results in one of the second force values meeting one of afirst threshold and a second threshold: first tactile feedback isprovided in response to detecting that at least one of the second forcevalue associated with the first touch and the second force valueassociated with the second touch meets a first threshold, and secondtactile feedback is provided when the second threshold is met by atleast one of the second force value associated with the first touch andthe second force value associated with the second touch, and neither thesecond force value associated with the first touch and the second forcevalue associated with the second touch meets the first threshold.

A method includes detecting a touch on a touch-sensitive display,determining when a force value associated with the touch meets a firstforce threshold, determining a first period of time between detectingthe touch when the force meets the first force threshold, and providinga first tactile feedback when the first period of time meets a firsttime threshold.

Another method includes detecting a touch on a touch-sensitive display,determining when a force value associated with the touch meets a secondforce threshold, after determining that the force value meets a firstforce threshold, determining a period of time between when the forcevalue meets the first force threshold and when the force value meets thesecond force threshold, and providing second tactile feedback when thesecond period of time meets a second time threshold.

An electronic device includes a touch-sensitive, an actuator configuredto provide tactile feedback, a force sensor configured to detect a forcevalue applied to the touch-sensitive display. The electronic device alsoincludes at least one processor operably coupled to the touch-sensitivedisplay, the actuator, and the force sensor, and configured to determinewhen a force value associated with the touch meets a first threshold,determine a first period of time between detecting the touch anddetermining when the force value associated with the touch meets thefirst threshold, and provide a first tactile feedback in response todetermining that the first period of time is greater than a firstpredetermined period of time.

The present disclosure may be embodied in other specific forms withoutdeparting from its spirit or essential characteristics. The describedembodiments are to be considered in all respects only as illustrativeand not restrictive. The scope of the present disclosure is, therefore,indicated by the appended claims rather than by the foregoingdescription. All changes that come within the meaning and range ofequivalency of the claims are to be embraced within their scope.

1. A method comprising: detecting a touch on a touch-sensitive display; determining when a touch value associated with the touch meets a first touch threshold; determining a first period of time between detecting the touch and when the touch value meets the first touch threshold; providing a first tactile feedback when the first period of time is meets a first time threshold.
 2. The method according to claim 1, wherein the first tactile feedback comprises simulation of depression of a switch.
 3. The method according to claim 1, comprising providing the first tactile feedback only when the first period of time meets the first time threshold.
 4. The method according to claim 1, comprising: determining when the touch value meets a second touch threshold, after the touch value meets the first touch threshold; determining a second period of time between when the touch value meets the first touch threshold and when the touch value meets the second touch threshold; providing second tactile feedback in response to determining that the second period of time meets a second time threshold.
 5. The method according to claim 4, wherein the second tactile feedback comprises simulation of release of a switch.
 6. The method according to claim 4, comprising providing the second tactile feedback only when the second period of time meets the second time threshold.
 7. A computer-readable medium having computer-readable code executable by at least one processor of a portable electronic device to perform the method of claim
 1. 8. A method comprising: detecting a touch on a touch-sensitive display; determining when a touch value associated with the touch meets a second touch threshold, after determining that the touch value meets a first touch threshold; determining a period of time between when the touch value meets the first touch threshold and when the touch value meets the second touch threshold; providing second tactile feedback when the second period of time meets a second time threshold.
 9. An electronic device comprising: a touch-sensitive display; an actuator configured to provide tactile feedback; at least one processor operably coupled to the touch-sensitive display and the actuator and configured to: determine when a touch value associated with the touch meets a first touch threshold; determine a first period of time between detecting the touch and determining when the touch value meets the first touch threshold; provide first tactile feedback in response to determining that the first period of time is greater than a first predetermined period of time.
 10. The electronic device according to claim 9, comprising one or more force sensors operably coupled to the processor, wherein the touch value is a force value.
 11. The electronic device according to claim 9, wherein the actuator comprises one or more piezoelectric actuators.
 12. The electronic device according to claim 9, wherein the first tactile feedback comprises simulation of depression of a switch.
 13. The electronic device according to claim 9, wherein the at least one processor is configured to: determine when the touch value meets a second touch threshold, after determining that the touch value meets the first touch threshold; determine a second period of time between determining when the touch value for the touch meets the first touch threshold and determining when the touch value for the touch meets the second touch threshold; provide a second tactile feedback in response to determining that the second period of time is greater than a second predetermined period of time. 